It is currently impossible to patch tcpip.sys in SP1. Microsoft has digitally signed the driver and checks it upon boot up. Patching the file in SP1 will prevent you from booting your system, even into safe mode. Fortunately, there's a work around. Go to mydigitallife and download the cracktcpip.sys driver. You have to manually install it, but documentation is provided and quite easy. Basically, cracktcpip.sys runs parallel to tcpip.sys and monitors the memory address that limits half-open connections to 10 in Vista. Because the value is only two digits in hex, cracktcpip.sys can only change the maximum half-open connections to 255, but hey, I'm not complaining now that I can use my browser along side my torrent client again. I've tested it on un-vlited x32 Vista as well as vlited x32 Vista, and the only error I've found in Event Viewer is under security, Event ID 5038 (System Integrity; image hash is invalid or corrupt). Eset Nod32 doesn't consider the file a threat, either. Until my school provides me with a free copy of Server 2008 (which doesn't have a connection limit), I'll be using Vista with cracktcpip.sys.